Energy conditions and current acceleration of the universe

Abstract

The energy conditions provide a very promising model-independent study of the current acceleration of the universe. However, in order to connect these conditions with observations, one often needs first to integrate them, and then find the corresponding constraints on some observational variables, such as the distance modulus. Those integral forms can be misleading, and great caution is needed when one interprets them physically. A typical example is that the transition point of the deceleration parameter $q(z)$ is at about $z\simeq 0.76$ in the $\Lambda$CDM model. However, with the same model when we consider the dimensionless Hubble parameter $E(z)$, which involves the integration of $q(z)$, we find that $E(z)$ does not cross the line of $q(z)=0$ before $z=2$. Therefore, to get the correct result, we cannot use the latter to determine the transition point. With these in mind, we carefully study the constraints from the energy conditions, and find that, among other things, the current observational data indeed strongly indicate that our universe has ocne experienced an accelerating expansion phase between the epoch of galaxy formation and the present.

revtex4, five figures. Corrected some typos and added new references. Physics Letters B652, 63-68 (2007)

References in corpus (11)

• Dynamics of dark energy
• Reconstructing Dark Energy
• Can dark energy evolve to the Phantom?
• WMAP constraints on low redshift evolution of dark energy
• Energy conditions in the epoch of galaxy formation
• Reconstruction of the deceleration parameter and the equation of state of dark energy
• Energy Conditions and Cosmic Acceleration
• Reconstruction of Hessence Dark Energy and the Latest Type Ia Supernovae Gold Dataset
• Energy Conditions and Supernovae Observations
• Accelerating cosmologies tested by distance measures
• SNLS data are consistent with acceleration at z=3

Cited by in corpus (27)

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• New Modified Mimetic Gravity
• Tolman-Oppenheimer-Volkoff equations in non-local $f(R)$ gravity
• Energy conditions in $f(T)$ gravity with non-minimal torsion-matter coupling
• Direct evidence of acceleration from distance modulus redshift graph
• Energy conditions bounds and their confrontation with supernovae data
• Dark energy and cosmic curvature: Monte-Carlo Markov Chain approach
• Energy conditions bounds and supernovae data
• Charged Compact Stars in Extended $f(\mathcal{R},\mathcal{G},\mathcal{T})$ Gravity
• Non-existence of Extended Holographic Dark Energy with Hubble Horizon
• Null tests with Gaussian Process
• Impact of curvature based geometric constraints on $F(R)$ theory
• Constraints on Dark Energy Models from Weak Gravity Conjecture
• Cosmology In Terms Of The Deceleration Parameter. Part II
• Energy Conditions in Extended $f(R,G,T)$ Gravity
• Energy Conditions in $f(P)$ Gravity
• Pseudo-Scalar Field as a Possible Candidate for Phantom Field
• Cosmic acceleration and the Hubble tension from baryon acoustic oscillation data
• Nilpotency Property, Physicality Criteria, Constraints and Standard BRST Algebra: A 4D Field-Theoretic System
• Bounding the Hubble flow in terms of the w parameter
• A $3D$ Field-Theoretic Model: Discrete Duality Symmetry
• Modified 3D Massive Abelian 2-From Theory with a Single Pseudo-Scalar Field as a Phantom Field: BRST Approach
• Cylindrically Symmetric Scalar Field and its Lyapunov stability in General Relativity